Designed for oligonucleotide therapeutic development and manufacturing

Seamlessly scale up your synthesis of siRNA and ASO for RNA therapeutics from early-stage development to commercial manufacturing with a comprehensive portfolio of Thermo Scientific TheraPure 2’ modified RNA phosphoramidites and TheraPure customization capabilities.

Modifications at the 2′ position of the ribose ring are commonly used to help increase oligonucleotide stability and improve resistance to nuclease activity in vivo. Thermo Scientific 2'-modified RNA phosphoramidites are manufactured to precise standards to ensure quality, consistency, and reliability for efficient synthesis of nucleic acid-based therapeutics.

Partner with us to access:

  • Expert technical support—over 40 years of partnership, customization, and scale-up experience
  • Secure and consistent supply—5x capacity expansion in 2022
  • Service excellence—48-hour or less response to orders and >98% delivery to customer at promised date
  • Flexible packaging—custom and bulk packaging available upon request
  • Quality—ISO 9001:2015–certified quality management system that has evolved in partnership with our customers over 25 years

To order:

  • Standard formats—pack sizes compatible with common oligo synthesizers are readily available to order online. First, locate the 2’ modification of interest, then select your synthesizer. Expand the appropriate ordering table below to choose the appropriate catalog number, and then add the item to your cart.
  • TheraPure custom services—for larger volumes, flexible packaging (custom and bulk), custom manufacturing services, or specialty phosphoramidites, contact our customer support team.

Overview of standard 2’ modified RNA phosphoramidites by synthesizer compatibility

2’ modificationCommon applicationModified baseApplied Biosystems/AKTA SynthesizerExpedite SynthesizerMerMade Synthesizer
2'-OMesiRNA 2'-OMe-Bz-AContact us
2'-MOEASO2'-MOE-AContact us
2'-OMe - FAST deprotectDiagnostics2'-OMe-PAC-A

2'-OMe Phosphoramidites - TheraPure and standard products

TheraPure (and standard) 2′-OMe phosphoramidites are presented in the table below.  For faster deprotection times, consider reviewing the PAC chemistries in combination with 2'-OMe U (no base protection) and Ac-rC.

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TheraPure phosphoramidites Cat. No.27-204227-204427-204627-2043
Cat. No.27-184227-182527-184627-1823
Molecular weight887.97 g/mol760.8 g/mol869.9 g/mol801.86 g/mol
CAS #110782-31-5110764-79-9150780-67-9199593-09-4
AppearanceColor intensity must not exceed Pantone #P1-4U or #P4-2U
HPLC purity (TheraPure phosphoramidites)≥ 98.0% | (>99%) *
M-11 Impurity≤ 0.01%
31P NMR purity (TheraPure phosphoramidites)≥ 98.0% | (>99%) *
Shipping / Storage  conditionAmbient / –20 °C
Water content ≤ 0.2% (KF Method)
Material OriginNon-animal source (no TSE/BSE risk)

2'-Fluoro Phosphoramidites - TheraPure and standard products

RNA oligonucleotides synthesized using 2′-Fluoro Bz A, iBu G, Ac C, and U phosphoramidites have increased thermal stability of RNA duplexes and nuclease resistance of single-stranded RNA. These phosphoramidites can be incorporated into custom siRNA oligonucleotides for use in gene-targeting and suppression studies.

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 2′-Fluoro-Bz-A-CEP2′-Fluoro-iBu-G-CEPTheraPure 2′-Fluoro-Ac-C-CEPTheraPure 2′-Fluoro-U-CEPTP 2'-Fluoro-Ac-G-CEP
Cat. No.27-160127-160727-160427-1602SY5410*
Molecular weight875.92 g /mol857.4 g/mol789.8 g/mol748.8 g/mol829.87 g/mol
CAS #NA144089-97-4159414-99-0146954-75-8N/A
AppearanceWhite to light yellow powder
HPLC purity*>98%
31P NMR purity*>98%
Residual SolventN/A≤ 3.0% total % by weight solvent
Solution ClarityFree from undissolved particulate at 0.2M solution in ACN
Shipping / Storage conditionAmbient / –20 °C
Water content≤ 0.3%
Material OriginNon-animal source (no TSE/BSE risk)

TheraPure 2’-MOE Phosphoramidites

RNA oligonucleotides synthesized using 2′-MOE modifications phosphoramidites have shown to be more nuclease resistant, with lower toxicity, and slightly increased hybridization affinities, making them well suited for therapeutic in vivo applications, such as antisense (ASO), siRNA, and aptamers. 

  • Tightly controlled, critical impurities (e.g., M-11)
  • Suitable for use with DNA and/or RNA phosphoramidites
  • Reliable, high quality oligonucleotide synthesis

  Click images to enlarge

Cat. No.27-101927-102027-102227-1021
Molecular weight932.03 g/mol922.0 g/mol914.01 g/mol819.0 g/mol
CAS #251647-53-7163759-94-2251647-55-9163878-63-5
Solution ClarityFree from undissolved particulate at 0.2M solution in ACN
HPLC purity*

 ≥ 99%

31P NMR purity*≥ 99%
Shipping / Storage  conditionAmbient / –20 °C
Water content≤ 0.3% (by KF Method)
Total residual solvents≤ 4.0%
Material OriginNon-animal source (no TSE/BSE risk)


2'-OMe Phosphoramidites - FAST deprotection

Utilize PAC-A and iPrPAC-G with Ac-C and U to minimize deprotection times.  Acetylated amidites (such as Ac-G, SY5400) are ideal for shortening deprotection times for longmers.

 2′-OMe-PAC-A-CEP2′-OMe-iPrPAC-G-CEPTheraPure 2'-OMe-Ac-G-CEP
Cat. No.27-182227-1826SY5400
Molecular weight918.0 g/mol976.1 g/mol841.9 g/mol
CAS #128219-82-9NA909033-40-5
HPLC purity≥ 98.0%≥ 98.0%≥ 99%
31P NMR purity≥ 98.0%≥ 98.0%≥ 99%
Shipping / Storage  conditionAmbient / –20 °C
Material OriginNon-animal source (no TSE/BSE risk)

Quality manufacturing and regulatory documentation

Processes are monitored from material procurement through final QC and product release, providing batch-to-batch reproducibility. Purity of each 2'-modified RNA phosphoramidite lot is assessed by HPLC and 31P NMR analyses. Our rigorously controlled manufacturing processes minimize levels of reactive P(III) impurities which could be incorporated into the oligonucleotide during synthesis and result in the accumulation of by-products.

Related areas

Phosphoramidites for nucleic acid synthesis – Find additional product portfolios including DNA phosphoramidites, dye-labeled phosphoramidites, and linkers and spacers.

For Research Use Only. Not for use in diagnostic procedures.